USA Trends and Developments Contributed by: Matthew K. Edling, Sher Edling
The regulatory landscape for 1,4-dioxane is develop- ing and evolving rapidly. In November 2024, the EPA issued a final Unreasonable Risk Determination for 1,4-Dioxane, stating that, “EPA has determined that 1,4-dioxane presents an unreasonable risk of injury to health under the conditions of use”. It continued: “EPA’s final determination is based on cancer and non-cancer risks… to workers and occupational non- users (ONUs) from inhalation and dermal exposures, and cancer risks to the general population, including fenceline communities, from exposures to 1,4-diox- ane in drinking water sourced from surface water con- taminated with industrial discharges of 1,4-dioxane (including when it is generated as a byproduct).” That determination was made during the Biden Administration pursuant to the process for conduct- ing chemical risk evaluations outlined under the Toxic Substances Control Act. Under the Trump Administra- tion, EPA Administrator Zeldin proposed a substantial revision to that rule, and the impact of that process on EPA’s view of 1,4-dioxane could change as a result. More on that below. In addition to evolving regulatory frameworks at the federal level, states are beginning to regulate 1,4-dioxane. In 2020, New York established an MCL for 1,4-dioxane in drinking water at 1 part per billion (ppb), the first state to do so. This is the most strin- gent enforceable standard for this chemical in drinking water in the nation. New York also has separate regu- lations for 1,4-dioxane limits in consumer products, with a lower limit for household cleaning and personal care products than for cosmetics. California and New Jersey are considering doing the same and have ini- tiated their respective processes for that considera- tion. It is presumed that other states are beginning to investigate their options and needs related to the contaminant. While 1,4-dioxane contamination of groundwater may not be as ubiquitous as PFAS contamination, treat- ing it is extremely expensive. Conventional treatment methods like granular activated carbon (GAC) - which water systems use to remove PFAS - cannot success- fully remove 1,4-dioxane. Instead, 1,4-dioxane remov- al requires an advanced oxidation process (AOP) fol-
lowed by removal with GAC of the by-products of AOP treatment. This two-step process involves high capital investment up front, in addition to substantial ongoing operating and maintenance costs. In December 2017, the Suffolk County Water Author- ity (SCWA) filed a lawsuit against the Dow Chemical Company, Ferro Corporation, Vulcan Materials Corpo- ration, Proctor & Gamble, and Shell Oil Company, over 1,4-dioxane contamination in the Long Island ground- water that supplies drinking water to approximately 1.2 million residents. SCWA is the largest water pro- vider on Long Island, and the largest water provider in the United States relying entirely on groundwater supply. Dow was the largest producer of dioxane- stabilised TCA in the United States; Ferro was one of Dow and Vulcan’s largest dioxane suppliers; and P&G and Shell manufactured some of the most popular dioxane-containing consumer products on the mar- ket, including Tide laundry detergent. SCWA’s complaint alleges that the defendants knew or should have known that the industrial degreas- ers, laundry detergents and other household prod- ucts they made, distributed or sold are dangerous to human health and contain unique characteristics that cause extensive and persistent environmental con- tamination. SCWA has resolved its case against some of the defendants, and earlier this year, the Court (Gershon, J) denied virtually all of the defendants’ Daubert and summary-judgment motions, refusing to exclude any of SCWA’s experts or to dismiss its claims for pub- lic nuisance, failure to warn and trespass. SCWA v Dow Chem Co , No 17-CV-6980 (NG) (JRC), 2025 WL 1907206 (E.D.N.Y. 10 July 2025). In March 2023, New Jersey Attorney General Mat- thew Platkin filed a lawsuit against the Dow Chemi- cal Company, Ferro Corporation and Vulcan Materials Company for widespread 1,4-dioxane contamination across New Jersey, becoming the first state in the nation to do so. The complaint alleges that the defendants “knowing- ly and willfully manufactured, promoted, and/or sold products containing 1,4-dioxane” in New Jersey with
411 CHAMBERS.COM
Powered by FlippingBook